Prior to going to Cuba illegally with three friends, a continuing subject of our speculative conversation was the stamp question. Do they or don’t they stamp your passport?

It turns out, they don’t. But it didn’t matter.

I got caught, anyway.

Actually, it was somewhat intentional.

Our group did what an estimated 20,000 to 50,000 other Americans do. That is, to enter Cuba through a third country without asking for the permit supposedly required by the U.S. State Department…more on that word “supposedly” later.

A friend, given all our passport information, bought our Cubana air tickets from Nassau to Havana, $189.50 round trip. In Nassau, we stood in line for well over an hour to get passes to board an ancient 142-passenger, Russian Yak 42 airplane.

The trip to Havana took a little more than an hour but it was an adventure in itself. Smoke came up in the floorboards under seats D4, 5 & 6 soon after takeoff. The floppy passenger seats would never meet FAA standards. The familiar flight attendant admonition to buckle up was also missing, and there were no references to any flotation devices anywhere (did we even have them?). But the plane ride was very smooth.

Upon arrival at the Jose Marti International Airport, we found the Cubans don’t stamp passports, arriving or leaving. Instead, visitors get a small exit visa, which is kept by Cuban customs officials on departure.

Leaving Cuba without incident, but with a lot of memories of friendly people and a crumbling society, we flew Cubana back to Nassau. It was another packed but smooth flight.

Arriving in Nassau, we filled out the usual forms saying where we had been. Illegal travelers generally cite Nassau and leave Cuba out.

My companions did and quickly cleared U.S. Customs in Nassau. With more than a little trepidation but emboldened by a free rum and Coke on the plane, I wrote that my last destination had been “Havana, Cuba.” I was immediately directed to a stern-faced, stiff-backed, mustachioed U.S. custom official.

After he greeted me, he demanded: “Where is your permit?”

“I don’t have one,” I stammered.

“Did you know it’s illegal for Americans to enter Cuba without a permit?”

“Uh, vaguely,” I answered.

He thoroughly searched my two carry-on bags, finding nothing from Cuba. Then he lectured me that the fine for my illegal entry was up to $2500 (not to mention up to ten years in prison).

“Next time, get a permit,” he advised.

But the confusing nature of illegal travel to Cuba does not end there. On my return, I read an article in Business Week magazine that said it’s no longer necessary to get a permit, which had been confusing.

Technically, travel to Cuba for Americans has never been banned. But it’s illegal to spend money there. So travelers have been told if they pre-pay for their trip, it’s OK.

“But these same rules (posted at www.treas.gov/ofac) say that full-time professionals whose travel is directly related to professional research can go without special permission. If they’re questioned by U.S. Customs agents, they can simply say they were legally entitled to go,” the article said.

Previously, Americans who fell into the professional category had to apply for a license, but the requirement was waived after the State Department was deluged with requests, according to the magazine.

Apart from the obvious categories of journalist and academic, all kinds of people now qualify. Washington requires only that the trip “comprises a full work schedule” and that the result “has a substantial likelihood of public dissemination.”

Since the latter has not been fully defined, the presumption is that publishing a traveler’s diary on the Internet or even writing a letter meets the requirement. And apparently there are no known cases of Americans prosecuted as “illegal.”

If you want my advice about going to Cuba, don’t forget to bring lots of cash. U.S. credit cards are worthless there.

As far as how you get there, far be it from me to promote illegality. In my opinion, however, a government continuing to single out one country in the world as forbidden to American travelers deserves to have its dubious wishes denied by any available loophole.